


The grand soulmate swap

by RussianSunflower3



Series: Sunflower's Seijou week [4]
Category: Haikyuu!!
Genre: Cream Puffs, Duo//Pairings, Friendship, Gen, Seijou Week
Language: English
Status: Completed
Published: 2016-03-17
Updated: 2016-03-17
Packaged: 2018-05-27 04:53:40
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,572
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6270340
Author URL: https://archiveofourown.org/users/RussianSunflower3/pseuds/RussianSunflower3
Summary: <blockquote class="userstuff">
              <p>It runs in the Oikawa family to be sly and cunning.<br/>Hence, Takeru challenges his uncle and his friends to swap in their duos.</p>
<p>This can only turn out disastrous.</p>
            </blockquote>





	The grand soulmate swap

“Makki, no!” 

“Aaaaah~.”

“Makki, I’m serious!”

“ _Aaaaah~_.” 

“MAKKI!” The cream puff Oikawa had been saving for after practice was gone in two rapid bites, swallowed down by one Hanamaki Takehiro. With all fairness, there was a written rule in the clubroom that any cream puffs on the premises were left alone at their own risk. Which is exactly why Oikawa had left the clubroom for _five minutes_ to find their Coach, and come back to Hanamaki rooting through his bag and pulling out the cream puffs. He comically sobbed as they disappeared into the oblivion of Hanamaki’s stomach.

“Why, Makki, why!? Iwa-chan would ever do this to me!” 

“Iwa-chan isn’t here though, is he~?” That was true. Iwaizumi was already off in the gym, setting up the nets with Matsukawa. Usually, that would be Hanamaki. Oikawa pouted as he wondered how it had come to this, before scowling as he realised it was his own – and his nephews – fault. He’d invited his friends over for a movie whilst babysitting Takeru, when he had raised a fair point.

_It was pretty cosy in Oikawa’s bedroom, with Oikawa himself lying on the bed flicking through a Volleyball Monthly, Iwaizumi and Hanamaki challenging each other on the Nintendo Wii, and Matsukawa sitting at the desk with little Takeru on his lap, helping the kid with his homework. Apart from the sounds of competition, there wasn’t much noise at all._

_“Why do you always hang around in pairs?” All eyes landed on the youngest Oikawa, who didn’t even pause in his homework before carrying on speaking._

_“You’re always Makki and Mattsun, or Uncle and Zoomi-nii.” The nickname drew snickers as Iwaizumi looked off out the window and pretended he wasn’t blushing. Oikawa scoffed on the bed, taking his glasses off to chew on one of the bits that hooked over his ear._

_“And what did you suggest, dear nephew of mine?” Takeru turned to look at him with scary intensity, the same Oikawa had when he was about to serve a vicious attack._

_“Swap.”_

That had been that. Under Takeru’s instructions, they had mixed thing up a little in their duos. Oikawa must have been a fool for accepting, and an even bigger fool for not bagsying Matsukawa, who wouldn’t have stolen his cream puffs! Childishly, he stomped his foot.

“I was saving those for after practice!”

“Harsh. Too bad. Sorry not sorry.” Hanamaki smirked as Oikawa spun on foot and marched back towards the gymnasium. He picked up the water bottle Oikawa had initially come back to collect, and followed with a skip in his step. It was the third day of the swap, and Hanamaki wasn’t complaining about the current company. He just... Missed his best friend. Spending time with his other friends was great, but it felt like he was missing part of his soul when Matsukawa was taken from his routine. Still, Takeru’s little ‘game’ didn’t say anything against _all four_ of them hanging out together. That made practice easier.

“Look out!” As soon as he stepped through the gymnasium doors, Hanamaki found himself with a ball in his hands, having caught it after it wildly deflected from someone’s warm up receives. He blinked before calmly throwing it back to Matsukawa with a slight smirk.

“Still not as good as me, huh?”

“Shut up. I’m better at blocking, and I’m smarter too.” Hanamaki stuck his tongue out in reply to the middle blocker. Iwaizumi received the ball volleyed towards him with a casual hum of thought.

“If you’re smarter, why are you in class 1?”

“Smarter _at volleyball_ , Iwaizumi. Generally I’m not for academics.” 

“Ah. That makes sense.” 

“Yes, you can’t all be intellectual like me~.” Oikawa appeared with a volleyball in one hand, and slung the other over Iwaizumi’s shoulders causing him to miss a receive and take a light spike to the face. A growl had Oikawa retreating to a safe distance. Due to their new schedule, spending less time together, when they were in the same general area, everything seemed more intense. They bantered more, at increasing violent and insulting levels. But they were softer and sappier in the rare moments of calm, flying from one extreme to the other.

“You’re only a class above me, Shittykawa! Stop letting it feed your ego, your head is big enough an’ ugly enough anyways!” Hanamaki and Matsukawa shared a look and sighed. Seemed like it was one of those days.

“Alright, that’s enough.” Oikawa found arms hooking around his waist and dragging him backwards, so he pouted and flopped into it, looking up at Hanamaki’s exasperated face. Iwaizumi was undergoing similar treatment, except Matsukawa’s eyes suddenly widened and he _lifted Iwaizumi up_ under the arms.

“OI!”

“What the fuck, you’re so light! How much do you weigh?!”

“Only 2kg less than you, don’t be stupid! I’m not light!” Matsukawa frowned and lifted him higher. 

“We’re going to the steakhouse after practice.”

“I’m a vegetarian, idiot.”

“... Ramen place, then. You can get your _‘Shoyu without the pork’_ as per usual. Or Agedashi Tofu.” Iwaizumi huffed, folding his arms.

“Fine.” As soon as he was on the ground, he stormed over to the cart of balls and started relentlessly spiking them against the wall. If one lost control and went flying off, he’d just grab another. Oikawa sighed, before jostling the ball on his hip.

“Makki! Mattsun! Let’s warm up with _‘Free For All’_!” With identical shit-eating grins, they snickered. Oikawa’s name for this particular warm up always due forth reactions from the team. He set the ball into the air, far enough away that someone would have to move to get it. Matsukawa managed to get into position and send the ball up high, perfect for Hanamaki to spike towards Oikawa, forcing him to dive for it. Luckily, with this game, it didn’t matter where the ball went. The ‘loser’ was whoever was closest to the ball when it hit the ground. Occasionally, with the third years being as mischievous as they were, they would purposely get lower and lower until it was physically impossible for someone to get the ball up.

“Good luck with this one!” Hanamaki lunged forwards and used a single fist to whack the ball straight up, but it careened off towards the gym entrance instead of staying in their singled out area. It bounced off Kindaichi’s head as he entered, too enthusiastically speaking to Kunimi to have even noticed the ball coming towards him. Kunimi caught it on the rebound and snickered at the off-guard, surprised look on his friends face. 

“You’re supposed to hit it with your arms, not your head.”

“I- I wasn’t paying attention!” The duo entered, Kunimi calmly passing the ball over to Matsukawa. Suddenly, he felt a chill down his spine. He turned blankly to face Oikawa who was watching him closely, a scheming glint to his eyes.

“Kunimi-chan, you and Kin-chan are always together, aren’t you~?” The first year raised an eyebrow in query. Oikawa was plotting something; that was for sure. Something devious.

“Most of the time. Sometimes I’ll go with Watari and he’ll go with Yahaba.” Oikawa stroked his chin, as if petting a goatee. 

“Hehehe~.” The repetitive rhythm of a ball being smacked against a wall paused. Iwaizumi looked over his shoulder.

“Oikawa, no.”

“Oikawa, yes~.”

“ _No._ ” Just as the second years entered, Oikawa struck a dramatic pose where he pointed between the duos. 

“You guys! You’re gonna do what Takeru made us do! Swap! Kindaichi, Watari, you are now a dynamic duo! Yahaba, Kunimi, you’re the duo of death!” Two scary glares were fired his way at the nickname and he shuddered, ducking behind Hanamaki for ‘protection’. Still, nobody complained and they appeared to obey. In those designated pairs, they warmed up with a back and forth volley-dig routine. Iwaizumi came out of his sulk to rejoin the ‘Free for all’ amongst the third years. A sharp piercing whistle broke through the peaceful warm up. 

“Gather round! We’ll be doing notices first, then serving practice!” They gathered around the coaches as Irihata gave them important information, including the match line up for the Spring Preliminaries. Their current focus on serving was a testament to how worried Irihata had been when he measured up the stats. Karasuno hadn’t had a server that stood out, but they were all strong. Their main concern was if #12 managed to master his jump float serve. 

“Serving practice again?” Kunimi groaned lightly as he moved into position. Oikawa snickered and nudged him with an elbow.

“You don’t want to be the weakest on the team, do you~?” A half-glare was delivered to Oikawa before they started practice. Mizoguchi watched curiously, noting that Iwaizumi was on the opposite side of the net to Oikawa, and Matsukawa opposite Hanamaki. Briefly, he wondered if they’d had a fight and sides had been taken, or if _both_ duos had fought. Mizoguchi made note to ask them after practice. Petty issues tearing apart the team were **not** a risk they could take. Especially when a controversial member of the team was meant to be returning soon. He’d only mentioned it to Oikawa recently, warning the setter that he would be dealing with a double-edged sword. However, his current concerns...

“That’s only 50% of your serves making the cut! I’m not impressed! From this point on, I want three serves in a row, over that net and within the court lines, or there’ll be a penalty of 25 sit-ups!” 

“Geh!” Distracted by the announcement, and a little offended by it, Oikawa missed the pinnacle of the serve toss and ended up putting the ball directly in the centre of the net. Irihata sent him a stern look, to which he groaned and lay on the floor, placing his hands behind his head. 

“1... 2... 3...”

“68, 42, 103, 16, 12!”

“Makki, no!” He lost count somewhere around the teens and begrudgingly started over from 10, trying to tune out Hanamaki next to him. He pulled himself to his feet and grabbed another volleyball, serving it just within the corners of the court. It wasn’t where he had been aiming, but it was powerful, Kindaichi yelping as the ball rebounded off the floor and smacked his bare leg.

“Sorry, Kin-chan!” Practice continued as such, going from serving practice to blocking to spiking. By the end of it, a particularly Spartan training session, the sweaty teenagers retreated to the club room in various states of exhaustion. Showering off in the facilities and changing into casual clothes they’d brought with them, they started to filter away. In the end, only the third years remained. Oikawa gave a petulant whine as he dropped onto a bench.

“I’m so bored of walking home without Iwa-chan... Iwa-chan, walk me home!” 

“You know that means accepting Takeru’s forfeit, right?” Oikawa froze with a slightly terrified, mostly pissed off expression. He’d forgotten that his nephew was just as crafty as himself.

_All four of them laughed at Takeru’s proclamation, Matsukawa letting the boy slip from his lap to stand in the centre of the room._

_“What do you mean by ‘swap’~? We can’t exactly change bodies, y’know?” Oikawa’s tone was light and teasing, but then Iwaizumi held out a flat hand in a gesture for the others to regain themselves._

_“Now hold on. Let the kiddo speak.” He crouched down to Takeru’s eye level._

_“What are you thinking of, Takeru?” Something dangerous glinted in Takeru’s eyes, a devious glimmer that Iwaizumi had seen many times before in his best friends, before he committed a prank with great consequence, or said something vaguely genius in a demonic way. The same spark that appeared whenever he was faced with Kageyama Tobio._ ‘Well, shit.’ __

_“Makki goes with Uncle, Mattsun goes with Zoomi-nii!”_

_“Yeah, like that’s so hard.”_

_“For a week!” Hanamaki and Matsukawa were cool about it, but Iwaizumi cast a hesitant look towards Oikawa, who he surprisingly found returning it. Since they had become_ bestest friends ****_at the tender age of seven, they had been separated for an entire week **once**. Even then it was supposed to be two weeks, but Iwaizumi had thrown a tantrum until his parents brought him home._

_“Okay, little man. But what if we don’t?” Takeru grinned._

_“If you don’t do it, or give up before the week is over, you have to_ shave your heads, legs, and wear spaghetti-strap dresses. For the rest of the year! _” The kid was evil, Iwaizumi would admit. Oikawa suddenly felt bad for ever teaching Takeru ‘all the tricks of the trade’._

“... How’s he gonna know?!”

“He’s related to you. He’ll somehow know.” Oikawa grimaced and ground his teeth together. A supportive hand squeezed his shoulder. He looked up to find Matsukawa giving him a smug look.

“Sorry for stealing your best friend, but I’m sure Makki will walk you home. Riiiight~?” All eyes turned to Hanamaki. Matsukawa’s smug pair, Oikawa’s pleading, and Iwaizumi genuinely curious as to his answer. He thought hard.

“Alright, fine. But you owe me a cream puff.”

“You literally _just ate the one I’d been **saving**!!!_ ” 

“Oh yeah. Well, consider your debt paid.” Oikawa pouted, but allowed Hanamaki to steer him out of the clubroom and towards home. Matsukawa huffed as soon as the door closed behind them, buttoning up his shirt and rolling the sleeves up. Iwaizumi’s lips twitched upwards at the checker print in varying hues of blue.

“You look like a Western cowboy in that.”

“Thanks.” Iwaizumi didn’t seem to pick up the sarcasm as he shrugged and pulled on a bright orange t-shirt with Godzilla destroying a city on the front.

“You look like a nerd in that.”

“Hey! I’m not a nerd! I just... Happen to like it.”

“Mhm. Yeah. Just like Oikawa likes Aliens.” Iwaizumi threw his sweaty number 4 shirt over at Matsukawa, but he just snickered, caught it, and threw it back. He slung his bag over his shoulder.

“Come on. Let’s go to Kadoya.” Iwaizumi instantly perked up, eyes widening with a bright twinkle of pure glee. 

“Seriously?! It’s after 5, it’ll be 2,400 Yen each!” 

“Seriously. I’ll pay every yen. It’s the only place you eat _everything_ at, and they’re happy to make it vegetarian.” Iwaizumi jogged after him, secretly excited. Things seemed to clink into place for the rest of the week.

Somehow, by the skin of their teeth, they survived. When Oikawa finished teaching Takeru at Lil Tykes Volleyball Classroom on the following Monday, the child declared that he was satisfied with the results and announced an end to their ‘soulmate swap’. Oikawa instantly marched him home, and then _galloped_ over to Iwaizumi’s. He didn’t need to knock, considering he’d been given a spare key at the start of high school.

“Iwa! Chan! IwachanIwachanIWACHAN!” 

“ _WHAT?_ ” He didn’t hesitate a single second before running through the house to tackle Iwaizumi as he came stomping down the stairs.

“O- Oikawa?!” His arms squeezed tighter around the Ace, pulling his tight grin out of Iwaizumi’s shoulder to excitedly babble.

“It’s over, Iwa-chan, Takeru said it’s over and now I can be with my best _best **best**_ friend again, and I never realised how much I need you before, Iwa-chan!” Rolling his eyes as Oikawa latched back into the hug, Iwaizumi couldn’t keep down the small smile on his lips.

“Yeah, I missed you too, Kusokawa. A duo isn’t the same without you.”


End file.
